Isolation of putative embryo-specific genes using stress induction of carrot somatic embryos

Abstract

Little is known about the physiological responses of higher plant cells during the early stages of embryogenesis and the genes that are involved in these responses. Carrot is an appropriate plant for the study of somatic embryogenesis as a model of zygotic embryogenesis. The system of stress induction of carrot somatic embryogenesis is useful for isolating genes expressed during embryogenesis, as embryogenic competence and the expression of certain embryo-specific genes increases with increased stress. Fluorescent differential display (FDD) was performed to isolate stress-induced genes in carrot somatic embryos, and five genes were isolated as embryonic tissue-specific genes. One of these genes was expressed until the early torpedo-shaped stage of zygotic embryogenesis. This result suggested that in the stress-induction system of carrot somatic embryos, embryo-specific genes expressed in the early stages of embryogenesis were induced during somatic embryo induction by stress treatment, concomitant with acquisition of embryonic competence. Unique genes expressed during early embryogenesis can be isolated from carrot by combining the appropriate experimental system and FDD. This strategy could be applied to many plant species for which genome information is not yet available.

Cryopreservation enhances embryogenic capacity of Gentiana cruciata (L.) suspension culture and maintains (epi)genetic uniformity of regenerants

“…It has been reported, for example, for Daucus carota or Festuca rubra , that somatic embryogenesis can be induced on primary explants (Kamada et al 1993 ; Tanaka et al 2009 ) or restored to long-term cultures (Zaghmout and Torello 1992 ), by the treatment with high levels of sucrose. In all the studies on cryopreservation, where elevation of embryogenic capacity was noticed, a prefreezing treatment with high concentrations of sucrose (Wang et al 2002 ; Winkelmann et al 2004 ; Engelmann et al 1997 ; Aguilar et al 1993 ) or sorbitol (Wang et al 1994 ) was used.…”

SET domain-containing protein genes are involved in Arabidopsis thaliana embryogenesis

“…In carrots, it is known that embryogenesis-related genes are induced by various kinds of stress treatments (Nishiwaki et al 2000;Kikuchi et al 2006), and novel embryogenesis-related genes have reportedly been isolated using this system (Tanaka et al 2009). In Arabidopsis, somatic embryos were formed on shootapical-tip explants by osmotic stress and 2,4-D, but no somatic embryos were induced on 2-week-old rosette leaf explants.…”